Background: Opioid misuse is a growing crisis in cancer patients. Cancer patients at risk of aberrant drug behaviors (ADB) are frequently underdiagnosed in routine cancer care. The aim of this study was to determine the frequency and factors associated with ADB using the “Screener and Opioid Assessment for Patients tool” (SOAPP-14) in cancer patients seen at the outpatient supportive care center. We also examined the screening performance of Cut Down, Annoyed, Guilty, and Eye Opener (CAGE-AID) as compared to The SOAPP-14 as a gold standard. Methods: In this retrospective study, 1108 consecutive patients referred to supportive care clinic were reviewed. Patients were eligible if they were ≥18 yrs, have a diagnosis of cancer, and were on opioids for pain for atleast a week. Patients’ demographics, the Edmonton Symptom Assessment Scale (ESAS), SOAPP-14, and CAGE-AID scores were analyzed. ADB+ was defined as SOAPP-14 score ≥7. Descriptive statistics, spearman correlation coefficient, multivariate, and ROC analysis were performed. Results: 703/1108 consults were eligible. A total of 153/703 (22%) were ADB +ve. SOAPP-14 scores were positively correlated with CAGE-AID r = .38, p < 0.001; male gender r = 0.11, p = 0.003; ESAS pain r = 0.11, p = 0.005; ESAS depression r = 0.22, p < 0.001; ESAS anxiety r = 0.22, p < 0.001, and ESAS financial distress r = 0.23, p < 0.001. Multivariate analysis indicated that the odds ratio for ADB +ve was 6.18 in patients with CAGE-AID+ (p < 0.001), 1.8 for male gender (p = 0.007), 1.1/pt. for ESAS anxiety (p = 0.044), and 1.1/pt. for ESAS financial distress (p = 0.007). A CAGE-AID score of 1/4 has a sensitivity of 47%, specificity of 89% positive predictive value 63.6% and negative predictive value 69.2%. Conclusions: Our study suggests that 22% of cancer patients on opioids presenting to supportive care center are at risk of aberrant drug behavior (ADB). Male patients with anxiety, financial distress, and prior alcoholism/illicit drug use are significant predictors of ADB’s. A cut off score of ≥1 out 4 on CAGE-AID questionnaire allows better screening of ADB in outpatient advanced cancer patients. Further research to effectively manage these patients is needed.